Hydrogen sulfide is an important gasotransmitter in plants that has been shown to aid in the survival of plants during environmental stressors such as droughts and high levels of salt in soil. Because hydrogen sulfide is a gas and toxic at high concentrations, delivery of hydrogen sulfide to plants is achieved by using chemicals that degrade to release hydrogen sulfide. The common chemicals used for this include sodium sulfide and GYY-4137. Sodium sulfide releases hydrogen sulfide too quickly to be applicable, and although GYY-4137 offers a more sustained release, the byproducts are not naturally found in the environment. Additionally, these chemicals are not easily tuned to control the rate of release of hydrogen sulfide. A series of dialkyldithiophosphates were synthesized using different alkyl alcohols or thiols. Upon addition to water, these chemicals had a sustained and slow release of hydrogen sulfide. The rate of release of hydrogen sulfide was easily tuned by changing the alkyl group. Degradation products from these chemicals included phosphoric acid and the corresponding alcohols, which are both natural chemicals depending on the alcohol used. Rate constants of the degradation of each chemical were obtained at elevated temperatures. The rates varied by four orders of magnitude, giving rise to easily accessible chemicals with vastly different hydrogen sulfide releasing properties, an important characteristic for the future of hydrogen sulfide releasing chemicals in the field of agriculture. To show the potential of these dialkyldithiophosphates in agriculture, peas were treated with dibutyldithiophosphate and the weight of the pea plant increased by 43% at a small loading of 1 mg per plant.

Utilizing the diverse hydrogen sulfide release properties of dialkyldithiophosphates for applications in agriculture

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.